In a work area wherein production processes are controlled, large numbers of instruments (for example, sensors and devices such as valve positioners) are located throughout the plant in order to control the processes. In a system for controlling these instruments, the instrument information regarding each individual instrument is collected into a controlling device for centralized control. However, when an instrument has been swapped by the production floor side where the instrument is installed, without notifying the administrator, then there will be a discrepancy between the instrument information that is controlled by the controlling device and the instrument information for the instrument that is installed on the production floor, which may become an impediment to control. For example, in the control system set forth in Japanese Unexamined Patent Application Publication No. 2009-205243 (“the JP '243”), if there is a difference between instrument information that is obtained for an individual instrument and instrument information that is controlled by the controlling device, the controlling device updates, with the instrument information that has been obtained from the instrument, the instrument information that is controlled.
In the control system set forth in the JP '243 above, when, for example, an instrument has been swapped by the production floor side on its own, a state wherein there is a discrepancy in the instrument information between the controlling device and the instrument will continue until the controlling device obtains instrument information from the instrument after the swap, to update that information, and thus there is room for improvement.
The present invention was created in order to solve the problems in the conventional technology set forth above, and an aspect thereof is to provide an instrument controlling device and instrument controlling method able to update, easily and promptly, the instrument information controlled by the system even when an instrument has been swapped without notifying the administrator.